[Subcellular distribution of Mn2+ and its effects on the respiration of rat liver mitochondria in different thyroid states].

Manganese concentration has been measured in the different subcellular fractions of live cells of normal and thyroidectomized rats. Results show that the quantity of Mn2+ taken up is smaller in the mitochondria and larger in the nuclei of the hypothyroid animals. When manganese is added to isolated mitochondria, an activation of mitochondrial respiration occurs and this activation is greater in thyroidectomized animals.